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CONNECTING THE PIPING
CONNECTION
(1) Install the outdoor unit wall cap (supplied with the optional installation set
or procured at the site) to the wall pipe.
(2) Connect the outdoor unit and indoor unit piping.
(3) After matching the center of the fl are surface and tightening the nut hand
tight, tighten the nut to the specifi ed tightening torque with a torque wrench.
(Table 1)
FLARING
(1) Cut the connection pipe to the necessary
length with a pipe cutter.
(2) Hold the pipe downward so that cuttings will
not enter the pipe and remove the burrs.
(3) Insert the fl are nut onto the pipe and fl are
the pipe with a fl aring tool.
Insert the fl are nut (always use the fl are nut
attached to the indoor and outdoor units re-
spectively) onto the pipe and perform the fl are
processing with a fl are tool.
Use the special R410A fl are tool, or the conv-
entional (for R22) fl are tool.
When using the conventional fl are tool, always
use an allowance adjustment gauge and secure
the A dimension shown in table 2 .
BENDING PIPES
(1) When bending the pipe, be careful not to crush it.
(2) To prevent breaking of the pipe, avoid sharp bends.
Bend the pipe with a radius of curvature of 2-13/16° (70mm) or
over.
(3) If the copper pipe is bend the pipe or pulled to often, it will become stiff.
Do not bend the pipes more than three times at one place.
AIR PURGE
Always use a vacuum pump to purge the air.
Refrigerant for purging the air is not charged in the
outdoor unit at the factory.
Close the high pressure side valve of the gauge manifold fully and do
not operate it during the following work.
1.
Check if the piping connections are secure.
2.
Check that the stems of 2-way valve and 3-way valve are closed fully.
3.
Connect the gauge manifold charge hose to the charging port of the
3-way valve (side with the projection for pushing in the valve core).
4.
Open the low pressure side valve of the gauge manifold fully.
5.
Operate the vacuum pump and start pump down.
6.
Slowly loosen the fl are nut of the 3-way valve and check if air enters,
then retighten the fl are nut.
(When the fl are nut is loosened the operating sound of the vacuum
pump changes and the reading of the compound pressure gauge goes
from minus to zero.)
7.
Pump down the system for at least 15 minutes, then check if the compound
pressure gauge reads -0.1 MPa (30 in.Hg ).
8.
At the end of pump down, close the low pressure side gauge of the gauge
manifold fully and stop the vacuum pump.
9.
Slowly loosen the valve stem of the 3-way valve. When the compound pres-
sure gauge reading reaches 0.1-0.2 MPa (14.5~28.9 psi), retighten the valve
stem and disconnect the charge hose from the 3-way valve charging port.
(If the stem of the 3-way valve is opened fully before the charge hose
is disconnected, it may be diffi cult to disconnect the charge hose.)
Additional charge
Refrigerant suitable for a piping length of 49 ft (15 m) is charged in the
outdoor unit at the factory.
When the piping is longer than 49 ft (15 m), additional charging is necessary.
For the additional amount, see the table below.
Pipe length
Additional refrigerant
3
Check if [L] is fl ared uniformly
and is not cracked or scratched.
Die
A
Pipe
49 ft (15 m)
66 ft (20 m)
None
+3.5 oz (+100 g)
0.2 oz/ft (20 g/m)
Tighten with two wrenches.
Torque
wrench
Indoor unit pipe
Table 1 Flare nut tightening torque
Flare nut
1/4" (6.35 mm) dia.
3/8" (9.52 mm) dia.
Table 2 Pipe outside diameter
Pipe outside
diameter
1/4" (6.35 mm)
3/8" (9.52 mm)
(1) Fasten a fl are nut with a torque wrench as instructed in this manual. If
fastened too tight, the fl are nut may be broken after a long period of time
and cause a leakage of refrigerant.
(2) During installation, make sure that the refrigerant pipe is attached fi rmly
before you run the compressor. Do not operate the compressor under the
condition of refrigerant piping not attached properly with 2-way or 3-way
valve open. This may cause abnormal pressure in the refrigeration cycle
that leads to breakage and even injury.
(1)
Refrigerant must not be discharged into atmosphere.
(2)
After connecting the piping , check the joints for gas
leakage with gas leak detector.
10. Fully open the valve stems of the 2-way valve and 3-way valve using a hexagon
wrench. (After the valve stem begins to turn, turn it with a torque of less than
2.9 N • m (30 kgf • cm) until it stops turning.)
11. Firmly tighten the 2-way valve and 3-way valve blank cap and the charg-
ing port cap.
3-way valve
Charging port cap
Blank cap
Charging port cap
(1)
When adding refrigerant, add the refrigerant from the
charging port at the completion of work.
(2)
The maximum length of the piping is 66 ft (20 m). If
the units are further apart than this, correct operation
Rate
can not be guaranteed.
Between 49 ft (15 m) and 66 ft (20 m), when using a connection pipe other than that
in the table, charge additional refrigerant with 0.2 oz/ft (20 g/m) as the criteria.
Wrench (fi xed)
Flare nut
To prevent gas leakage, coat the fl are
Connection pipe
surface with refrigerator oil.
Tightening torque [N·m (lbt·ft)]
16 to 18 (11.8 to 13.3)
32 to 42 (23.6 to 31.0)
A [in (mm)]
Conventional (R22) fl are tool
Flare tool for
R410A, clutch type
Clutch type
0 to 1/32 (0 to 0.5)
1/32 to 2/32 (0.5 to 1.5)
0 to 1/32 (0 to 0.5)
1/32 to 2/32 (0.5 to 1.5)
CAUTION
CAUTION
Gauge manifold
Compound pressure gauge
-0.1 MPa
2-way valve
(30 in.Hg )
Flare nut
Low prossure
side valve
Valve stem
Blank cap
Charge hose
Charging port
Tightening torque [N·m (lbt·ft)]
20 to 25 (14.8 to 18.4)
10 to 12 (7.4 to 8.8)
CAUTION
Wing nut type
2/32 to 3/32 (1.5 to 2.0)
2/32 to 3/32 (1.5 to 2.0)
Pressure gauge
High
pressure
side valve
(closod)
Charge
hose
Vacuum pump
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